private static LunarCoordinates GetMoonCoords(double[] LDMNF, double t, double JD)
{
LunarCoordinates cel = new LunarCoordinates();
// Legacy function. Updated with Meeus Calcs for increased accuracy.
// geocentric ecliptic coordinates of the moon
// Meeus Ch 47
double[] cs = Get_Moon_Coordinates(LDMNF, t);
double l = cs[0]; // longitude
double b = cs[1]; // latitude
double geocentricLongitude = l.ToDegrees();
cel.julianDayDecimal = JD - .5 - Math.Floor(JD - .5);
cel.latitude = b.ToDegrees();
cel.rightAscension = RightAscension(l, b).ToDegrees().NormalizeDegrees360();
cel.declination = Declination(l, b).ToDegrees();
cel.geometricMeanLongitude = LDMNF[0].NormalizeDegrees360();
//APPARENTS
//Get longitutde of the acsencing node of the moon's mean orbit on the ecliptic, measure from the mean equinox of the date
double lngAscendingNode = 125.04452 - 1934.136261 * t;
double la = lngAscendingNode.ToRadians();
//Mean Longitudes
double sunL = 280.4665 + 36000.7698 * t;
double moonL = 218.3165 + 481267.8813 * t;
cel.sunMeanLongitude = sunL.NormalizeDegrees360();
//nutations in longitude
double lngNutation = (-17.20).ToSeconds() * Math.Sin(la) - (1.32).ToSeconds() * Math.Sin(2 * sunL) - (.23).ToSeconds() * Math.Sin(2 * moonL) + (.21).ToSeconds() * Math.Sin(2 * la);
cel.longitude = geocentricLongitude + lngNutation;
////nutations in obliquity
//double obNutation = (9.20).ToSeconds() * Math.Cos(la) + (.57).ToSeconds() * Math.Cos(2 * sunL) + (.10).ToSeconds() * Math.Cos(2 * moonL) - (.09).ToSeconds() * Math.Cos(2 * la);
////Obliquity of the ecliptic 22.2 (MAY NEED TO SWITCH TO 22.3 in future as it is higher accuracy)
//double U = t / 100;
//double E0 = Format.ToDegrees(23, 23, 21.488) - (46.8150).ToSeconds() * t - (.00059).ToSeconds() * Math.Pow(t, 2) + (.001813).ToSeconds() * Math.Pow(t, 3);
//double E = E0 + obNutation; //true Obliquity
return(cel);
}
public static void GetMoonIllumination(DateTime date, Celestial c, double lat, double lng, EagerLoad el, double offset)
{
//Moon Illum must be done for both the Moon Name and Phase so either will trigger it to load
if (el.Extensions.Lunar_Cycle || el.Extensions.Zodiac)
{
date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, DateTimeKind.Utc);
offset *= -1;
double julianOffset = offset * .04166667;
SolarCoordinates s = SunCalc.Get_Solar_Coordinates(date, offset);
double JDE = JulianConversions.GetJulian(date) + julianOffset; //Get julian
double T = (JDE - 2451545) / 36525; //Get dynamic time.
double[] LDMNF = Get_Moon_LDMNF(T);
LunarCoordinates m = GetMoonCoords(LDMNF, T, JDE);
double sdist = 149598000,
phi = Math.Acos(Math.Sin(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) + Math.Cos(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians())),
inc = Math.Atan2(sdist * Math.Sin(phi), 0 - sdist * Math.Cos(phi)),
angle = Math.Atan2(Math.Cos(s.declination.ToRadians()) * Math.Sin(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()), Math.Sin(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) -
Math.Cos(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()));
MoonIllum mi = new MoonIllum();
mi.Fraction = (1 + Math.Cos(inc)) / 2;
mi.Phase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI;
mi.Angle = angle;
c.moonIllum = mi;
string moonName = "";
int moonDate = 0;
//GET PHASE NAME
//CHECK MOON AT BEGINNING AT END OF DAY TO GET DAY PHASE
DateTime dMon = new DateTime(date.Year, date.Month, 1);
for (int x = 1; x <= date.Day; x++)
{
DateTime nDate = new DateTime(dMon.Year, dMon.Month, x, 0, 0, 0, DateTimeKind.Utc);
s = SunCalc.Get_Solar_Coordinates(date, offset);
JDE = JulianConversions.GetJulian(nDate) + julianOffset; //Get julian
T = (JDE - 2451545) / 36525; //Get dynamic time.
LDMNF = Get_Moon_LDMNF(T);
m = GetMoonCoords(LDMNF, T, JDE);
phi = Math.Acos(Math.Sin(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) + Math.Cos(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()));
inc = Math.Atan2(sdist * Math.Sin(phi), 0 - sdist * Math.Cos(phi));
angle = Math.Atan2(Math.Cos(s.declination.ToRadians()) * Math.Sin(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()), Math.Sin(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) -
Math.Cos(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()));
double startPhase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI;
nDate = new DateTime(dMon.Year, dMon.Month, x, 23, 59, 59, DateTimeKind.Utc);
s = SunCalc.Get_Solar_Coordinates(date, offset);
JDE = JulianConversions.GetJulian(nDate) + julianOffset; //Get julian
T = (JDE - 2451545) / 36525; //Get dynamic time.
LDMNF = Get_Moon_LDMNF(T);
m = GetMoonCoords(LDMNF, T, JDE);
phi = Math.Acos(Math.Sin(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) + Math.Cos(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()));
inc = Math.Atan2(sdist * Math.Sin(phi), 0 - sdist * Math.Cos(phi));
angle = Math.Atan2(Math.Cos(s.declination.ToRadians()) * Math.Sin(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()), Math.Sin(s.declination.ToRadians()) * Math.Cos(m.declination.ToRadians()) -
Math.Cos(s.declination.ToRadians()) * Math.Sin(m.declination.ToRadians()) * Math.Cos(s.rightAscension.ToRadians() - m.rightAscension.ToRadians()));
double endPhase = 0.5 + 0.5 * inc * (angle < 0 ? -1 : 1) / Math.PI;
//Determine Moon Name.
if (startPhase <= .5 && endPhase >= .5)
{
moonDate = x;
moonName = GetMoonName(dMon.Month, moonName);
}
//Get Moon Name (month, string);
//Get Moon Phase Name
if (date.Day == x)
{
if (startPhase > endPhase)
{
mi.PhaseName = "New Moon";
break;
}
if (startPhase <= .25 && endPhase >= .25)
{
mi.PhaseName = "First Quarter";
break;
}
if (startPhase <= .5 && endPhase >= .5)
{
mi.PhaseName = "Full Moon";
break;
}
if (startPhase <= .75 && endPhase >= .75)
{
mi.PhaseName = "Last Quarter";
break;
}
if (startPhase > 0 && startPhase < .25 && endPhase > 0 && endPhase < .25)
{
mi.PhaseName = "Waxing Crescent";
break;
}
if (startPhase > .25 && startPhase < .5 && endPhase > .25 && endPhase < .5)
{
mi.PhaseName = "Waxing Gibbous";
break;
}
if (startPhase > .5 && startPhase < .75 && endPhase > .5 && endPhase < .75)
{
mi.PhaseName = "Waning Gibbous";
break;
}
if (startPhase > .75 && startPhase < 1 && endPhase > .75 && endPhase < 1)
{
mi.PhaseName = "Waning Crescent";
break;
}
}
}
if (date.Day == moonDate)
{
if (el.Extensions.Zodiac)
{
c.AstrologicalSigns.moonName = moonName;
}
}
else
{
if (el.Extensions.Zodiac)
{
c.AstrologicalSigns.moonName = "";
}
}
}
if (el.Extensions.Lunar_Eclipse)
{
CalculateLunarEclipse(date, lat, lng, c);
}
}
private static MoonPosition GetMoonPosition(DateTime date, double lat, double lng, Celestial cel, double offset, bool setCelC)
{
//Set UTC date integrity
date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, DateTimeKind.Utc);
double julianOffset = offset * .04166667;
//Ch 47
double JDE = JulianConversions.GetJulian(date); //Get julian
double oJDE = JulianConversions.GetJulian(date) + julianOffset; //Get julian
double T = (oJDE - 2451545) / 36525; //Get dynamic time.
double[] LDMNF = Get_Moon_LDMNF(T);
LunarCoordinates celC = GetMoonCoords(LDMNF, T, oJDE);
if (setCelC)
{
cel.lunarCoordinates = celC;
}
Distance dist = GetMoonDistance(date.AddHours(offset));
double lw = rad * -lng;
double phi = rad * lat;
double H = rad * MeeusFormulas.Get_Sidereal_Time(oJDE) - lw - celC.rightAscension.ToRadians();
double ra = celC.rightAscension.ToRadians(); //Adjust current RA formula to avoid needless RAD conversions
double dec = celC.declination.ToRadians(); //Adjust current RA formula to avoid needless RAD conversions
//Adjust for parallax (low accuracy increases may not be worth cost)
//Investigate
double pSinE = Get_pSinE(dec, dist.Meters) * Math.PI / 180;
double pCosE = Get_pCosE(dec, dist.Meters) * Math.PI / 180;
double cRA = Parallax_RA(dist.Meters, H, pCosE, dec);
double tDEC = Parallax_Dec(dist.Meters, H, pCosE, pSinE, dec, cRA);
double tRA = ra - cRA;
dec = tDEC;
ra = tRA;
//Get true altitude
double h = Altitude(H, phi, dec);
// formula 14.1 of "Astronomical Algorithms" 2nd edition by Jean Meeus (Willmann-Bell, Richmond) 1998.
double pa = Math.Atan2(Math.Sin(H), Math.Tan(phi) * Math.Cos(dec) - Math.Sin(dec) * Math.Cos(H));
//altitude correction for refraction
h += AstroRefraction(h);
MoonPosition mp = new MoonPosition();
mp.Azimuth = Azimuth(H, phi, dec);
mp.Altitude = h / Math.PI * 180;
mp.Distance = dist;
mp.ParallacticAngle = pa;
double horParal = 8.794 / (dist.Meters / 149.59787E6); // horizontal parallax (arcseconds), Meeus S. 263
double p = Math.Asin(Math.Cos(h) * Math.Sin(horParal / 3600)); // parallax in altitude (degrees)
p *= 1000;
mp.ParallaxCorection = p;
mp.Altitude *= rad;
return(mp);
}
